The present invention relates to a front body construction of a vehicle which is capable of absorbing effectively an impact force caused upon the vehicle crashing.
There are many known front body constructions of vehicles in the art. Generally, the known front body construction includes left and right front side frames extending lengthwise and connected to lower peripheries of left and right wheel houses, respectively, and left and right apron frames extending lengthwise and connected to upper peripheries of the left and right wheel houses, respectively. These front side frames and apron frames terminate at the same location in a lengthwise direction. One such front body construction is disclosed in, for example, Japanese Utility Model Unexamined Publication No. 55- 114,772.
Meanwhile, there are two somewhat conflicting requirements that govern the mechanical strength of front body construction and the ability of absorbing impact force upon a car crash. Specifically, the front body has to be resistant to road shock when traveling and, on the other hand, has to be liable to cause buckling or crushing in the front body upon a car crash. Because impact force produced upon a car crash is mainly absorbed by buckling or crushing caused in frames of the front body of a vehicle, if a frame work of the front body is designed to have an increased mechanical strength, it becomes more hard to absorb impact force exerted on the front body by the buckling or crushing caused in the frame and in such case of car crash, on the contrary, if designed to be apt to cause buckling, the front body becomes weak against road shock on ordinary driving.
In this regard, one disadvantage associated with the front body construction taught by the above mentioned Japanese Utility Model Unexamined Publication is that the front body construction having the front side and apron frames rigidly connected to each other at the same location in a lengthwise direction is too strong in mechanical strength and, thereby, difficult to cause easily buckling or crushing in order to absorb a frontal impact force upon a frontal car crash. For example, when a vehicle having such a front body crashes head on another vehicle or smashes into a solid construction, impact force received by the car body, in particular the front body, is simultaneously transmitted to and distributed in the front side frames and the apron frames. Owing to this distribution of impact force, these frames are hard to cause buckling, resulting in an insufficient ability of absorbing the frontal impact force.